package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.Follow;
import com.hmdp.mapper.FollowMapper;
import com.hmdp.service.IFollowService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.service.IUserService;
import com.hmdp.utils.UserHolder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;

import static com.hmdp.constants.RedisConstants.FOLLOW_KEY;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class FollowServiceImpl extends ServiceImpl<FollowMapper, Follow> implements IFollowService {
    @Autowired
    StringRedisTemplate stringRedisTemplate;
    @Autowired
    IUserService userService;
    @Override
    public Result isFollow(Long followUserId) {
        Long id = UserHolder.getUser().getId();
        int count = count(new LambdaQueryWrapper<Follow>().eq(Follow::getUserId, id).eq(Follow::getFollowUserId, followUserId));
        return Result.ok(count>0);
    }

    @Override
    public Result follow(Long followUserId, Boolean isFollow) {
        Long id = UserHolder.getUser().getId();
        String key = FOLLOW_KEY + id;
        if(isFollow){
           // 关注用户，新增数据
            Follow follow = new Follow();
            follow.setUserId(id);
            follow.setFollowUserId(followUserId);
            save(follow);
            stringRedisTemplate.opsForSet().add(key, followUserId.toString());
        }else{
            // 取关用户，删除一条数据
            remove(new LambdaQueryWrapper<Follow>().eq(Follow::getUserId, id).eq(Follow::getFollowUserId, followUserId));
            stringRedisTemplate.opsForSet().remove(key, followUserId.toString());
        }
       return Result.ok();
    }

    @Override
    public Result followCommon(Long userId) {
        Long curId = UserHolder.getUser().getId();
        // 1、通过redis得到共同的关注id
        Set<String> commonId = stringRedisTemplate.opsForSet().intersect(FOLLOW_KEY + curId, FOLLOW_KEY + userId);
        List<Long> idList = commonId.stream().map(Long::valueOf).collect(Collectors.toList());
        //2、查询用户信息
        List<Object> userDtoList = userService.query().in("id", idList)
                .list().stream().map(user -> BeanUtil.copyProperties(user, UserDTO.class))
                .collect(Collectors.toList());
        return Result.ok(userDtoList);
    }
}
